Takashi U. Ito

Identification of connexins in human oral mucosa and therapeutic effect of irsogladine maleate on aphthous stomatitis.

Abstract: We identified connexins 26 and 32 in human oral mucosa. The presence of the connexins indicates the presence of gap junctions in this tissue. However, immunofluorescence study found no significant differences in the expression of the connexins between patients with aphthons stomatitis and controls. Irsogladine maleate, which reinforces gap junctional intercellular communication in vitro, was effective for the treatment of transient and relapsing aphthous stomatitis, as well as symptomatic and drug-induced aphthous stomatitis. It was also useful for prevention of episodes of relapsing aphthous stomatitis, with daily administration preverting recurrence of stomatitis for more than 4 years one patient. These findings suggest that irsogladine maleate accelerates the wound healing process in oral mucosa by reinforcing gap junctional intercellular communication among oral mucosal cells; and that it is useful for the treatment and prevention of aphthous stomatitis.

Nondestructive Elemental Depth-Profiling Analysis by Muonic X-ray Measurement

Elemental analysis of materials is fundamentally important to science and technology. Many elemental analysis methods have been developed, but three-dimensional nondestructive elemental analysis of bulk materials has remained elusive. Recently, our project team, dreamX (damageless and regioselective elemental analysis with muonic X-rays), developed a nondestructive depth-profiling elemental analysis method after a decade of research. This new method utilizes a new type of probe; a negative muon particle and high-energy muonic X-rays emitted after the muon stops in a material. We performed elemental depth profiling on an old Japanese gold coin (Tempo-Koban) using a low-momentum negative muon beam and successfully determined that the Au concentration in the coin gradually decreased with depth over a micrometer length scale. We believe that this method will be a promising tool for the elemental analysis of valuable samples, such as archeological artifacts.

An Alignment of J-PARC Linac

J-PARC linear accelerator components are now being installed in the accelerator tunnel, whose total length is more than 400 m including the beam transport line to 3GeV synchrotron. A precise alignment of accelerator components is essential for high quality beam acceleration. In this paper, planned alignment schemes for the installation of linac components and watching the long term motion of the building are described. Markings are placed on the floor, which act as a reference for the initial alignment at the installation. For a straight line alignment, the wire position sensor is placed on the offset position with respect to the beam center by a target holder. The hydrostatic levering system is used for watching the floor elevation over the long period.

The Development of a Non-Destructive Analysis System with Negative Muon Beam for Industrial Devices at J-PARC MUSE

Motonobu Tampo1, Kouji Hamada1, Naritoshi Kawamura1, Makoto Inagaki2, Takashi U. Ito3, Kenji M. Kojima1, Kenya M. Kubo4, Kazuhiko Ninomiya2, Patrick Strasser1, Go Yoshida2 and Yasuhiro Miyake1 1Institute of Materials Structure Science, KEK, Tokai, Ibaraki 319-1195, Japan 2Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama Toyonaka, Osaka, 560-0043 Japan 3Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki, 319-1195, Japan 4International Christian University, Mitaka, Tokyo, 181-8585, Japan

Development of a Muon Linac for the G-2/EDM Experiment at J-PARC

We are developing a linac dedicated to the muon acceleration for muon g-2/EDM experiment at J-PARC. The muon linac consists of a radio-frequency-quadrupole (RFQ), an inter-digital H-mode (IH) drift tube linac (DTL), a diskand-washer (DAW) -type coupled cell linac (CCL), and a disk-loaded structure. This paper describes the design of each structure and current progress towards muon acceleration with the RFQ, which is expected to be the first practical realization of muon acceleration in the world.

Upgrade and Operation of J-PARC Linac

Kazuo HASEGAWA*, Hidetomo OGURI, Takashi ITO, Etsuji CHISHIRO, Koichiro HIRANO, Takatoshi MORISHITA, Shinichi SHINOZAKI, Hiroyuki AO, Kiyonori OHKOSHI, Yasuhiro KONDO, Jun TAMURA, Saishun YAMAZAKI, Toshihiko HORI, Fumiaki SATO, Yasuo NEMOTO, Isao KOIZUMI, Nobuo OUCHI, Nobuhiro KIKUZAWA, Akira UENO, Akihiko MIURA, Shinpei FUKUTA, Akinobu YOSHII, Koichi SATO, Akira OZONE, Yuki SAWABE, Yusuke KAWANE, Hiroshi IKEDA, Yuichi ITO, Yuko KATO, Kazuo KIKUCHI, Fumio HIROKI, Toshio TAKAYASU, Tsutomu USAMI, Munetoshi YANAI, Kazuhiko TADOKORO, Kenji OHSAWA, Fujio NAITO, Yong LIU, Zhigao FANG, Takashi SUGIMURA, Kenta FUTATSUKAWA, Kiyoshi IKEGAMI, Masato KAWAMURA, Kesao NANMO, Yuji FUKUI, Tomoaki MIYAO, Tomofumi MARUTA and Akira TAKAGI

Muonic atom formation processes for carbon containing molecules

Muonic atom is an atomic system which has a negative muon substituted an electron. Muonic atom formation processes are strongly influenced by the chemical environment of muon capturing atom such as molecular structure, however, the initial processes of muon capture still have not been well investigated. In this study, we performed muon irradiation for gaseous carbon containing molecules to investigate the chemical environmental effect on muon capture processes.

Magnetism in Ce2Rh(In,Sn)8 heavy-fermion compound

Measurements of muon spin relaxation have been performed on Ce2RhIn8?xSnx (x = 0.0,0.1,0.5 and 0.7) single crystals down to 0.3 K. A clear muon spin precession signal was observed in x = 0.0 and 0.1 samples due to antiferromagnetic ordering with magnetic volume fraction of ~75% below TN. While an increase of relaxation rate was observed in x = 0.5 below 0.5 K, no precession signal was observed, suggesting the suppression of antiferromagnetism with increasing Sn concentration.

μSR study of CeRhIn5 under applied pressure

At ambient pressure CeRhIn5 is an incommensurate antiferromagnet with N?el temperature TN = 3.8 K. The application of pressure reduces TN and yields (1) a state in which AFM coexists with superconductivity, and then (2) a superconducting state in the absence of AFM. We report transverse-field muon spin relaxation (?SR) measurements at pressures 2.07 and 2.26 GPa in the pure superconducting state of single-crystalline CeRhIn5, which has a tetragonal structure. ?SR is sensitive to the local field distribution produced by the vortex lattice in a mixed superconducting state, allowing a measurement of the magnetic field penetration depth ?(T). We measured ?ab(T) for applied field along the c-axis as a function of temperature T, and find ?ab(0) = 372(5) nm and 338(6) nm for P = 2.07 GPa and 2.26 GPa, respectively. The temperature dependence of the superfluid density ?s(T) ??2(T) was found to be ?s(T) Tn with n = 1.9(2).